Glass or no glass

[Skepperz]

Now I know you get a lot of evaporation without glass on top but does it hurt?

[jdtaz69]

Not as long as you top up regularly with fresh RO water. If you live in a hot climate or regularly go away for a few days you should either get a cover or install an auto-topup mechanism. If like me you live in the UK you won't need a cover... I top up twice a day with about half a litre of water each time (0.5% overall volume).

[yankeebobo]

The key is to keep up with the evap.

[Dubbin1]

Glass tops are going to hold a lot of heat in and not help any with the gas exchange. If you must have a top on the tank then the best way to go is egg crate.

[WaterKeeper]

Not only does it not harm anything but it is beneficial for the tank. Low air circulation on a tightly topped aquarium allows for the build-up of carbon dioxide under the cover. The forces down pH and can even lower dissolved oxygen levels. As Dwayne points out, the decreased evaporation rates on a topped aquarium also can lead to overheating. Sure you can have a top but it should be well ventilated and not sealing in gasses and heat.

[Ky_Yaker]

Just make sure you aren't stocking any fish that are known for jumping. Some people use egg crate on top of their tank to help with that issue.

[bheron]

i've had glass tops on my 75g for a few years. i'm going away form them with my 210 for the reasons listed above.